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1.
Epilepsy Behav ; 140: 109117, 2023 03.
Article in English | MEDLINE | ID: mdl-36804846

ABSTRACT

BACKGROUND: Psychogenic Non-Epileptic Seizures (PNES) and Functional Motor Disorders (FMDs) commonly represent the main clinical manifestations of Functional Neurological Disorders (FNDs). Despite their high prevalence in pediatric neurological services, literature on this topic is still spare for this population. The present study aimed to deepen the clinical knowledge of a pediatric FNDs sample through a demographic and clinical characterization of the most recurrent clinical patterns during the pediatric age. Moreover, a comparison of neuropsychological and psychopathological profiles of PNES and FMD patients was carried out to identify specific vulnerabilities and therapeutic targets linked with these different clinical manifestations. MATERIALS AND METHODS: A total of 43 FNDs patients (age range 7-17 years old) were retrospectively included in our study, enrolled in two subgroups: 20 with FMDs and 23 with PNES diagnosis. They were inpatients and outpatients referred over a period of 5 years and a standardized neurological, neuropsychological (WISC-IV/WAIS-IV), and psychiatric (CDI-2, MASC-2, ADES, DIS-Q, PID-5) evaluation was assessed. RESULTS: In PNES patients the most common clinical phenotypes were functional tonic-clonic (52%) and atonic (32%) manifestations while in the FMDs group were gait alterations (60%), functional myoclonus (35%), and tremor (35%). A higher frequency of cognitive impairment was reported in PNES patients with higher anxiety-depressive symptom rates than FMDs patients. CONCLUSIONS: Notably, specific neurocognitive and psychopathological profiles were described in PNES and FMDs, highlighting higher cognitive and psychiatric vulnerabilities in PNES, suggesting as well different strategy for therapeutic approaches.


Subject(s)
Conversion Disorder , Motor Disorders , Humans , Motor Disorders/diagnosis , Retrospective Studies , Seizures/complications , Seizures/diagnosis , Conversion Disorder/complications , Conversion Disorder/diagnosis , Anxiety/psychology , Electroencephalography
2.
Pulmonology ; 29 Suppl 4: S80-S85, 2023 Dec.
Article in English | MEDLINE | ID: mdl-34219041

ABSTRACT

INTRODUCTION AND OBJECTIVES: Subjects with severe acquired brain injury (sABI) require long-term mechanical ventilation and, as a consequence, the tracheostomy tube stays in place for a long time. In this observational study, we investigated to what extent the identification of late tracheostomy complications by flexible bronchoscopy (FBS) might guide clinicians in the treatment of tracheal lesions throughout the weaning process and lead to successful decannulation. SUBJECTS AND METHODS: One hundred and ninety-four subjects with sABI admitted to our rehabilitation unit were enrolled in the study. All subjects received FBS and tracheal lesions were treated either by choosing a more suitable tracheostomy tube, or by laser therapy, or by steroid therapy, or by a combination of the above treatments. RESULTS: Overall, 122 subjects (63%) were decannulated successfully. Our subjects received 495 FBSs (2.55 per subject) and as many as 270 late tracheostomy complications were identified. At least one complication was found in 160 subjects (82%). In only 11 subjects, late tracheostomy complications did not respond to the treatment and were the cause of decannulation failure. CONCLUSIONS: In conclusion, in sABI patients FBS is able to guide successful tracheostomy weaning in the presence of late tracheostomy complications that could get in the way decannulation.


Subject(s)
Brain Injuries , Tracheostomy , Humans , Bronchoscopy , Device Removal , Respiration, Artificial , Postoperative Complications , Brain Injuries/rehabilitation
3.
Eur Rev Med Pharmacol Sci ; 25(1): 161-164, 2021 01.
Article in English | MEDLINE | ID: mdl-33506904

ABSTRACT

Extramedullary hematopoiesis (EMH) is a proliferation of hematopoietic tissue outside the bone marrow. The most affected areas are paravertebral ones. We report the case of a patient with homozygous Hb Lepore, not regularly transfused since the age of four years until the age of 29 years, when paravertebral heterotopic masses were first observed. After about 10 years she started reporting clinical signs suggestive of sinusitis. Computed tomography (CT) and Magnetic Resonance Imaging (MRI) showed heterotopic masses in the ethmoid and in the frontal sinuses. Involvement of the sinuses of the large facial area represents a rare localization of EMH. Various cases have been reported in patients with thalassemia intermedia, but no case has been reported with HbLepore. The diagnostic gold standard is MRI, which provides highly accurate and clear images. The treatment is based on hydroxyurea and/or an intensive transfusional regime and sometimes on surgery.


Subject(s)
Frontal Sinus/diagnostic imaging , Hematopoiesis, Extramedullary , Hemoglobins, Abnormal/analysis , Magnetic Resonance Imaging , Tomography, X-Ray Computed , Adult , Female , Humans
5.
Respiration ; 86(6): 462-71, 2013.
Article in English | MEDLINE | ID: mdl-23428500

ABSTRACT

BACKGROUND: Breathing pattern description and chest wall kinematics during phonation have not been studied in male and female patients with chronic obstructive pulmonary disease. OBJECTIVES: We used optoelectronic plethysmography to provide a quantitative description of breathing pattern and chest wall kinematics. METHODS: Volumes of chest wall compartments (rib cage and abdomen) were assessed in 15 patients while reading aloud (R), singing (SI) and during high-effort whispering (HW). RESULTS: Relative to quiet breathing, tidal volume and expiratory time increased while inspiratory time decreased. The expiratory flow decreased during R and SI, but was unchanged during HW. In males, the end-expiratory volume decreased as a result of a decreased volume of rib cage during R, SI and HW and due to a decreased volume of abdomen during HW. In females, a decrease in end-expiratory volume was accomplished by a decrease in abdominal volume during R and HW. During R, the chest wall end-expiratory volume of the last expiration in females was to the left of the maximal expiratory flow volume curve (MEFV), with still substantial expiratory reserve volume available. In contrast, during SI and HW in females and during all types of phonation in males, chest wall end-expiratory volume of the last expiration was well to the right of the MEFV curve and associated with respiratory discomfort. Gender had a greater importance than physical characteristics in determining more costal breathing in females than in males under all conditions studied. CONCLUSIONS: Phonation imposes more abdominal breathing pattern changes in males and costal changes in females. Expiratory flow encroaches upon the MEFV curve with higher phonatory efforts and respiratory discomfort.


Subject(s)
Phonation/physiology , Pulmonary Disease, Chronic Obstructive/physiopathology , Respiratory Mechanics/physiology , Thoracic Wall/physiology , Aged , Biomechanical Phenomena/physiology , Female , Humans , Lung Volume Measurements , Male , Plethysmography/methods , Sex Factors
6.
Respir Physiol Neurobiol ; 186(1): 95-102, 2013 Mar 01.
Article in English | MEDLINE | ID: mdl-23348025

ABSTRACT

We hypothesized that arm training might affect unsupported arm exercise-related perception by decreasing motor output to arm/torso muscles in patients with chronic obstructive pulmonary disease (COPD). Eleven patients were studied at 80% of peak incremental arm exercise, before and after unsupported arm training. Training increased endurance time, decreased respiratory effort and much more arm effort (by Borg scale) without affecting chest wall dynamic hyperinflation or configuration. Ventilatory response to carbon dioxide output was the same before and after training so that at isotime the reduction in ventilation correlated strongly with a simultaneous reduction in metabolic output. These changes reflect a reduced ventilatory drive. We conclude that: (i) a reduced level of ventilation, relative to a decrease in central motor output, is the contribution of arm training to symptom alleviation during unsupported arm exercise in COPD patients, and (ii) arm training improved patients' exercise-related perception without affecting chest wall operational volumes or configuration.


Subject(s)
Arm/physiology , Dyspnea/rehabilitation , Exercise Therapy/methods , Perception , Pulmonary Disease, Chronic Obstructive/rehabilitation , Aged , Dyspnea/etiology , Female , Humans , Male , Pulmonary Disease, Chronic Obstructive/complications , Respiratory Function Tests
7.
Respir Physiol Neurobiol ; 183(2): 122-7, 2012 Aug 15.
Article in English | MEDLINE | ID: mdl-22688019

ABSTRACT

No data are available on the effects of the Nuss procedure on volumes of chest wall compartments (the upper rib cage, lower rib cage and abdomen) in adolescents with pectus excavatum. We used optoelectronic plethysmography to provide a quantitative description of chest wall kinematics before and 6 months after the Nuss procedure at rest and during maximal voluntary ventilation in 13 subjects with pectus excavatum. An average 11% increase in chest wall volume was accommodated within the upper rib cage (p=0.0001) and to a lesser extent within the abdomen and lower rib cage. Tidal volumes did not significantly change during the study. The repair effect on chest wall kinematics did not correlate with the Haller index of deformity at baseline. Six months of the Nuss procedure do increase chest wall volume without affecting chest wall displacement and rib cage configuration.


Subject(s)
Funnel Chest/surgery , Thoracic Wall/physiology , Thoracic Wall/surgery , Abdomen/physiology , Adolescent , Biomechanical Phenomena , Humans , Lung Volume Measurements , Male , Plethysmography/methods , Pulmonary Ventilation/physiology , Ribs/physiology , Thoracic Surgical Procedures/methods
8.
Respir Physiol Neurobiol ; 180(2-3): 211-7, 2012 Mar 15.
Article in English | MEDLINE | ID: mdl-22138611

ABSTRACT

Quantifying chest wall kinematics and rib cage distortion during ventilatory effort in subjects with Pectus excavatum (PE) has yet to be defined. We studied 24 patients: 19 during maximal voluntary ventilation (MVV) and 5 during MVV and cycling exercise (CE). By optoelectronic plethysmography (OEP) we assessed operational volumes in upper rib cage, lower rib cage and abdomen. Ten age-matched healthy subjects served as controls. Patients exhibited mild restrictive lung defect. During MVV end-inspiratory and end-expiratory volumes of chest wall compartments increased progressively in controls, whereas most patients avoided dynamic hyperinflation by setting operational volumes at values lower than controls. Mild rib cage distortion was found in three patients at rest, but neither in patients nor in controls did MVV or CE consistently affect coordinated motion of the rib cage. Rib cage displacement was not correlated with a CT-scan severity index. Conclusions, mild rib cage distortion rarely occurs in PE patients with mild restrictive defect. OEP contributes to clinical evaluation of PE patients.


Subject(s)
Funnel Chest/physiopathology , Thoracic Wall/physiopathology , Abdomen/anatomy & histology , Abdomen/physiology , Biomechanical Phenomena , Child , Exercise Test , Female , Funnel Chest/diagnostic imaging , Humans , Inspiratory Capacity/physiology , Lung Volume Measurements , Male , Plethysmography , Respiratory Function Tests , Ribs/physiology , Thoracic Wall/diagnostic imaging , Tidal Volume/physiology , Tomography, X-Ray Computed
9.
Eur Rev Med Pharmacol Sci ; 12(4): 251-6, 2008.
Article in English | MEDLINE | ID: mdl-18727457

ABSTRACT

The Helicobacter pylori (H. pylori) cure rate following standard triple therapies is decreasing worldwide. Therefore, further approaches aimed to improve standard triple therapy efficacy should be attempted. This prospective, pilot study aimed to evaluate the therapeutic role of either Lactobacillus reuteri (L. reuteri) or a high concentration of probiotics in addition to standard triple therapies for H. pylori eradication. The study enrolled 65 consecutive dyspeptic patients with H. pylori infection. All patients underwent upper endoscopy with gastric biopsies. Patients were assigned to receive one of the following therapies: (a) standard 7-day triple; (b) the same 7-day triple therapy plus L. reuteri supplementation; (c) the same 7-day triple therapy plus a probiotic mixture; and d) a 14-day standard triple therapy plus a probiotic mixture. H. pylori eradication was checked by using a 13C-urea breath test performed 4-6 weeks after treatment. No therapy regimen achieved > 80% eradication rate at both intention-to-treat (ITT) and per protocol (PP) analyses. Although the 14-day therapy plus a probiotic mixture tended to achieve higher eradication rate (71%), no statistically significant difference emerged among the different therapy regimens tested (range: 53-71%). The lowest incidence of side-effects was observed following the 7-day therapy plus L. reuteri (6%) and highest with the 14-day triple therapy plus probiotic mixture (33%), although the difference failed to reach the statistically significance. In conclusion, our data found that 7-14 days triple therapy with or without probiotic supplementation failed to achieved acceptable H. pylori eradication rates.


Subject(s)
Anti-Bacterial Agents/therapeutic use , Anti-Ulcer Agents/therapeutic use , Helicobacter Infections/drug therapy , Probiotics/therapeutic use , 2-Pyridinylmethylsulfinylbenzimidazoles/adverse effects , 2-Pyridinylmethylsulfinylbenzimidazoles/therapeutic use , Adult , Aged , Amoxicillin/adverse effects , Amoxicillin/therapeutic use , Anti-Bacterial Agents/adverse effects , Anti-Ulcer Agents/adverse effects , Clarithromycin/adverse effects , Clarithromycin/therapeutic use , Drug Therapy, Combination , Female , Follow-Up Studies , Helicobacter pylori/drug effects , Humans , Limosilactobacillus reuteri/chemistry , Lansoprazole , Male , Middle Aged , Pilot Projects , Probiotics/adverse effects , Prospective Studies
10.
Acta Physiol (Oxf) ; 193(4): 393-402, 2008 Aug.
Article in English | MEDLINE | ID: mdl-18363899

ABSTRACT

AIM: To test the hypothesis that obese individuals may either hyperinflate or deflate the lung when exercising. In both cases breathlessness is an inescapable consequence. METHODS: Ventilatory variables, end-expiratory lung volume and end-inspiratory lung volume, and dyspnoea score (Borg scale) were studied in 20 class II-III obese subjects and 14 healthy controls during incremental symptom-limited cycle exercise. RESULTS: Ventilation increased with increasing work rate, in obese and in control subjects; most obese subjects had to increase end-expiratory lung volume to escape from flow limitation; in contrast, like controls, a few subjects deflated the lung on heavy-to-peak exercise. Dyspnoea was equal in degree at anaerobic threshold and peak exercise in obese as in control subjects, and in obese who hyperinflated as in those who deflated the lung. In particular, end-expiratory lung volume at baseline (r = -0.84, P = 0.04) was negatively correlated with changes in Borg score in obese who did not hyperinflate: the lower the former the higher the latter. On the other hand, tidal volume (r = 0.54, P = 0.045) and decrease in inspiratory reserve volume (r = 0.59, P = 0.028) were positively correlated with the Borg score in obese subjects who hyperinflated. No other independent variable correlated with the Borg score. CONCLUSIONS: We conclude that not all obese subjects had to increase end-expiratory lung volume on heavy-to-peak exercise. Changes in dyspnoea for unit changes in ventilation were similar in obese who did hyperinflate as well as in those who did not, suggesting that the increase in respiratory neural drive, associated with an increase in ventilation, is an important source of dyspnoea in obese as well as in control subjects.


Subject(s)
Dyspnea/etiology , Exercise , Obesity/complications , Pulmonary Ventilation , Adult , Carbon Dioxide/blood , Dyspnea/physiopathology , Exercise Test , Female , Forced Expiratory Volume , Humans , Male , Middle Aged , Obesity/physiopathology , Obesity, Morbid/complications , Obesity, Morbid/physiopathology , Oxygen/blood , Partial Pressure , Total Lung Capacity
11.
Acta Physiol (Oxf) ; 190(4): 351-8, 2007 Aug.
Article in English | MEDLINE | ID: mdl-17394566

ABSTRACT

AIM: The study of kinematics of the chest wall (CW) could allow us to define the relative deflationary contribution of its compartments during fits of coughing. We hypothesized that if forces applied to the lung apposed rib cage are not commensurate with those applied to the abdomen-apposed rib cage, cough could result in rib cage distortion. METHODS: In 12 (five women) healthy subjects we evaluated the volumes of CW (Vcw) and its compartments: the lung apposed rib cage, the abdomen apposed rib cage and the abdomen, by optoelectronic plethysmography. The loop of volume of the lung apposed rib cage/volume of the abdomen apposed rib cage allowed the calculation of mean rib cage distortion, resulting in a dimensionless number which, when multiplied by 100, gives percentage distortion. Each subject performed voluntary single and prolonged coughing efforts at functional residual capacity (FRC) and after maximal inspiration (max). The normal level of mean distortion was set at <0.5%. RESULTS: The three compartments contributed to reducing end-expiratory Vcw during cough at FRC and prolonged maximum cough, with the latter resulting in the greatest CW deflation. Mean rib cage distortion did not differ between men and women (P > 0.1), but tended to significantly increase from single to prolonged Cough Max (1.3% +/- 1.0 vs. 2.3% +/- 1.6, respectively; P = 0.06). CONCLUSION: Rib cage distortion may ensue during coughing, probably as a result of uneven distribution of forces applied to the rib cage.


Subject(s)
Cough/physiopathology , Ribs/physiopathology , Thoracic Wall/physiology , Adult , Biomechanical Phenomena , Cough/pathology , Female , Humans , Male , Plethysmography , Respiratory Mechanics/physiology , Ribs/pathology , Thoracic Wall/pathology
12.
Acta Physiol (Oxf) ; 188(1): 63-73, 2006 Sep.
Article in English | MEDLINE | ID: mdl-16911254

ABSTRACT

AIM: We hypothesize that different patterns of chest wall (CW) kinematics and respiratory muscle coordination contribute to sensation of dyspnoea during unsupported arm exercise (UAE) and leg exercise (LE). METHODS: In six volunteer healthy subjects, we evaluated the volumes of chest wall (V(cw)) and its compartments, the pulmonary apposed rib cage (V(rc,p)), the diaphragm-abdomen apposed rib cage (V(rc,a)) and the abdomen (V(ab)), by optoelectronic plethysmography. Oesophageal, gastric and trans-diaphragmatic pressures were simultaneously measured. Chest wall relaxation line allowed the measure of peak rib cage inspiratory muscle, expiratory muscle and abdominal muscle pressures. The loop V(rc,p)/V(rc,a) allowed the calculation of rib cage distortion. Dyspnoea was assessed by a modified Borg scale. RESULTS: There were some differences and similarities between UAE and LE. Unlike LE with UAE: (i) V(cw) and V(rc,p) at end inspiration did not increase, whereas a decrease in V(rc,p) contributed to decreasing CW end expiratory volume; (ii) pressure production of inspiratory rib cage muscles did not significantly increase from quiet breathing. Not unlike LE, the diaphragm limited its inspiratory contribution to ventilation with UAE with no consistent difference in rib cage distortion between UAE and LE. Finally, changes in abdominal muscle pressure, and inspiratory rib cage muscle pressure predicted 62% and 41.4% of the variability in Borg score with UAE and LE, respectively (P < 0.01). CONCLUSION: Leg exercise and UAE are associated with different patterns of CW kinematics, respiratory muscle coordination, and production of dyspnoea.


Subject(s)
Dyspnea/physiopathology , Exercise/physiology , Respiratory Muscles/physiology , Thoracic Wall/physiology , Abdominal Muscles/physiology , Adult , Analysis of Variance , Arm , Biomechanical Phenomena , Esophagus/physiology , Humans , Leg , Linear Models , Male , Movement , Pressure , Pulmonary Gas Exchange , Respiratory Mechanics/physiology , Ribs , Stomach/physiology
13.
Acta Physiol (Oxf) ; 186(3): 233-46, 2006 Mar.
Article in English | MEDLINE | ID: mdl-16497202

ABSTRACT

AIMS: We used for the first time a non-invasive optoelectronic plethysmography to assess breathing movements and to provide a quantitative description of chest wall kinematics during phonation. METHODS: Volumes of different chest wall compartments (abdomen and lung apposed to rib cage and abdomen) were assessed using optoelectronic plethysmography in 16 normal Italians (eight men) during reading, singing and high-effort whispering (HW). RESULTS: During phonation the breathing pattern was different from quiet breathing and exercise. (1) During phonation, tidal volume and expiratory time increased while inspiratory time decreased. The expiratory volume changes and flows during HW were considerably greater than during vocalization. During HW, the overall end-expiratory thoracic volume significantly decreased as a result of decreased volume of all compartments and essentially impinged on the maximal expiratory flow-volume curve. (2) While, as previously shown, during exercise the expired volume is due entirely to the abdomen, during phonation all three chest wall compartments contribute to it. Under all conditions studied breathing was, on average, more costal in females than in males but this was mainly related to different size rather than gender per se. CONCLUSIONS: Physical characteristics have a greater importance than gender in determining breathing pattern and chest wall kinematics during phonation. The activity of the control of expiration during phonation is more complex than during exercise.


Subject(s)
Phonation/physiology , Respiratory Mechanics/physiology , Adult , Anthropometry , Biomechanical Phenomena , Exercise/physiology , Female , Forced Expiratory Volume/physiology , Humans , Male , Middle Aged , Plethysmography/methods , Respiratory Function Tests , Sex Characteristics , Thoracic Wall/physiology , Vital Capacity/physiology
14.
Eur Respir J ; 24(3): 453-60, 2004 Sep.
Article in English | MEDLINE | ID: mdl-15358706

ABSTRACT

No direct measurements of the pressures produced by the ribcage muscles, the diaphragm and the abdominal muscles during hyperventilation have been reported in patients with ankylosing spondylitis. Based on recent evidence indicating that abdominal muscles are important contributors to stimulation of ventilation, it was hypothesised that, in ankylosing spondylitis patients with limited ribcage expansion, a respiratory centre strategy to help the diaphragm function may involve coordinated action of this muscle with abdominal muscles. In order to validate this hypothesis, the chest wall response to a hypercapnic/hyperoxic rebreathing test was assessed in six ankylosing spondylitis patients and seven controls by combined analysis of: 1) chest wall kinematics, using optoelectronic plethysmography, this system is accurate in partitioning chest wall expansion into the contributions of the ribcage and the abdomen; and 2) respiratory muscle pressures, oesophageal, gastric and transdiaphragmatic (Pdi); the pressure/volume relaxation characteristics of both the ribcage and the abdomen allowed assessment of the peak pressure of both inspiratory and expiratory ribcage muscles, and of the abdominal muscles. During rebreathing, chest wall expansion increased to a similar extent in patients to that in controls; however, the abdominal component increased more and the ribcage component less in patients. Peak inspiratory ribcage, but not abdominal, muscle pressure was significantly lower in patients than in controls. End-inspiratory Pdi increased similarly in both groups, whereas inspiratory swings in Pdi increased significantly only in patients. No pressure or volume signals correlated with disease severity. The diaphragm and abdominal muscles help to expand the chest wall in ankylosing spondylitis patients, regardless of the severity of their disease. This finding supports the starting hypothesis that a coordinated response of respiratory muscle activity optimises the efficiency of the thoracoabdominal compartment in conditions of limited ribcage expansion.


Subject(s)
Respiratory Muscles/physiopathology , Spondylitis, Ankylosing/physiopathology , Thorax/physiopathology , Abdominal Muscles/physiopathology , Biomechanical Phenomena , Case-Control Studies , Humans , Hypercapnia/physiopathology , Middle Aged , Respiratory Function Tests
15.
Eur J Appl Physiol ; 91(5-6): 525-33, 2004 May.
Article in English | MEDLINE | ID: mdl-14735363

ABSTRACT

The present study was designed to verify whether during hypercapnic stimulation, as we had previously found during exercise or walking, the partitioning of the respiratory motor output is equally distributed to the muscles of chest wall compartments to assist diaphragm function. We studied chest wall kinematics and respiratory muscle recruitment in seven healthy men during rebreathing of a hypercapnic-hyperoxic gas mixture (CO(2) RT). Data were compared with those previously obtained during either cycling exercise or walking. The chest wall volume ( Vcw), assessed by optoelectronic plethysmography (OEP), was modeled as the sum of the volumes of the lung-apposed rib cage ( Vrc,p), diaphragm-apposed rib cage ( Vrc,a) and abdomen ( Vab). Esophageal ( Pes), gastric ( Pga) and transdiaphragmatic ( Pdi= Pga- Pes) pressures were simultaneously recorded. Velocity of shortening ( V') and power ( W'= Px V') of the diaphragm ( W'di), rib cage muscles ( W'rcm) and abdominal muscles ( W'abm) were also calculated. During CO(2) RT the progressive increase in end-inspiratory Vcw resulted from an increase in both end-inspiratory Vrc,p and Vrc,a, while the progressive decrease in end-expiratory Vcw was entirely due to the decrease in end-expiratory Vab. The increase in Vrc,p was proportionally slightly greater than that in Vrc,a. The end-inspiratory increase and end-expiratory decrease in Vcw were accounted for by inspiratory rib cage (RCM,i) and abdominal (ABM) muscle recruitment, respectively. W'di, W'rcm and W'abm progressively increased. However, while most of W'di was expressed in terms of velocity of shortening, most of W'rcm and W'abm was expressed as force or pressure. A comparison of CO(2) results with data obtained during exercise revealed: (1). a gradual vs. an immediate response, (2). a similar decrease in Vab,e and Pabm, (3). an apparent lack of any difference in ABM recruitment, (4). less gradual ABM relaxation, (5). no drop in Pdi but a similar Wdi change and decrease in pressure-to-velocity ratio of the diaphragm. We have found that in healthy humans: (1). the increased motor output with hypercapnia is equally distributed between RCM and ABM to minimize transdiaphragmatic pressure and (2). data on chest wall kinematics and respiratory muscle recruitment are only partly in line with those obtained during walking or cycling exercise.


Subject(s)
Abdominal Muscles/physiology , Hypercapnia/physiopathology , Postural Balance/physiology , Pulmonary Ventilation/physiology , Respiratory Mechanics/physiology , Respiratory Muscles/physiology , Thoracic Wall/physiology , Adult , Humans , Male
16.
Infect Immun ; 71(7): 3852-6, 2003 Jul.
Article in English | MEDLINE | ID: mdl-12819069

ABSTRACT

By using mouse models, it has been shown that Pneumocystis carinii f. sp. muris can be transmitted to immunocompetent mice that are exposed to immunosuppressed mice with active P. carinii pneumonia. We sought to determine whether P. carinii f. sp. muris could be transmitted between normal mice. The rationale for these experiments was to demonstrate whether the normal host could serve as the reservoir of organisms that produce Pcp when the organism is acquired by the immunosuppressed host. Under the conditions of these experiments, normal mice are able to be infected by brief cohousing with P. carinii-infected SCID mice. There was active replication of organisms in the normal host such that the organism could be transmitted to other normal mice, again with active replication. Mice that had seroconverted after exposure to P. carinii-infected SCID mice were more resistant to infection when reexposed. Infection in normal mice was well tolerated with minimal effects on dynamic lung compliance. We speculate, based on these results, that transmission from normal host to normal host, as an asymptomatic or minimally symptomatic infection, could be a way to maintain this opportunistic pathogen in the environment.


Subject(s)
Pneumonia, Pneumocystis/transmission , Animals , Immunocompetence , Lung Compliance , Mice , Mice, Inbred BALB C , Mice, SCID , Pneumocystis/isolation & purification , Pneumonia, Pneumocystis/immunology , Pneumonia, Pneumocystis/physiopathology , Polymerase Chain Reaction
17.
Respir Med ; 97(3): 197-204, 2003 Mar.
Article in English | MEDLINE | ID: mdl-12645825

ABSTRACT

In this review we shall consider the commonest techniques to reduce dyspnea that are being applied to patients with chronic obstructive pulmonary disease (COPD) subjected to a pulmonary rehabilitation program (PRP). Pursed lip breathing (PLB) and diaphragmatic breathing (DB) are breathing retraining strategies employed by COPD patients in order to relieve and control dyspnea. However, the effectiveness of PLB in reducing dyspnoea is controversial. Moreover, DB may be associated with asynchronous and paradoxical breathing movements, reflecting a decrease in the efficiency ofthe diaphragm. Exercise training (EXT) is a mandatory component of PRP.EXT has been shown to improve exercise performances and peripheral muscle strength. Recent studies have focused on the effect of EXT on breathlessness. However, concerns persist as to whether the decreased sensation of dyspnea for a given exercise stimulus is principally due to psychological benefits of rehabilitation or to improved physiological ability to perform exercise. The effect of EXT on breathlessness may be reinforced by inhaling oxygen. However, two studies have recently shown that breathing supplemental oxygen during training has either a marginal effect or no advantage over training. In a comprehensive PRP, strength training (ST) and arm endurance training (AET) could have a role in decreasing peripheral muscle weakness and metabolic and ventilatory requirements for AET. The role of unloading the respiratory muscles during EXT has to be


Subject(s)
Breathing Exercises , Pulmonary Disease, Chronic Obstructive/rehabilitation , Diaphragm/physiology , Humans , Oxygen/administration & dosage , Posture , Respiratory Muscles/physiology
19.
Lung ; 180(6): 349-57, 2002.
Article in English | MEDLINE | ID: mdl-12647236

ABSTRACT

Chest wall compartment kinematics and respiratory muscle coordinate activity, during either hypercapnia or hypoxia, have not been comparatively assessed in healthy humans. We assessed the displacement volume of the chest wall (Vcw) in 5 normal subjects during hypoxic-normocapnic and hypercapnic-hyperoxic rebreathing by using linearized magnetometers. Vcw was divided into displacement volumes of the rib cage (Vrc) and the abdomen (Vab). Esophageal (Pes) and gastric (Pga) pressures were simultaneously recorded and transdiaphragmatic pressure (Pdi) was calculated by subtracting Pes from Pga. Pressure swings (sw) from end expiration (EE) to end inspiration (EI) were also calculated. During both hypoxia and hypercapnia, from quiet breathing to 40 L/min VE, Vrc,EI increased consistently but Vrc,EE, and Vab,EI did not. Moreover, Vab,EE decreased significantly during hypercapnia and remained unchanged during hypoxia. PesEI decreased (more negative values) and PesEE increased (less negative values) during either stimulus, while PgaEE increased with hypercapnia. Pdisw, calculated as the difference between PdiEE and PdiEI, increased significantly with both hypercapnia and hypoxia ( p = 0.002 for both). On the plot of Pes vs Pga, the slope of a line from end expiratory to end inspiratory lung volume between 20 and 40 L/min VE progressively increased during hypercapnia indicating increasing rib cage muscle (RCM) contribution to inspiratory pressure swings relative to the diaphragm. From these results we conclude that in healthy man: (i) with both chemical stimuli RCM contribution accounts for increase in Vrc displacement; (ii) with hypercapnia, the decrease in Vab,EE displacement indicates abdominal muscle (ABM) contribution to tidal volume; (iii) RCM and ABM assist the diaphragmatic function during hypercapnic stimulation.


Subject(s)
Hypercapnia/physiopathology , Hypoxia/physiopathology , Respiratory Mechanics , Respiratory Muscles/physiology , Adult , Biomechanical Phenomena , Humans , Male
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